Classifying device



Jan. 5, 1960 F. P. ROBBINS 2,

CLASSIFYING DEVICE Filed Sept. 20, 1957 3 Sheets-Sheet l Jan. 5, 1960 F.P. ROBBINS 2,91

CLASSIFYING DEVICE Filed Sept. 20, 1957 3 Sheets-Sheet 2 INVENTOR:FREDERICK P. ROBBINS ATT YS Jan. 5, 1960 F. P. ROBBINS CLASSIFYINGDEVICE 3 Sheets-Sheet 3 Filed Sept. 20, 1957 INVENTOR: FREDERICK F?ROBBINS ATT' Y S United States Patent if CLASSIFYING DEVICE Frederick P.Robbins, Highland "Park, Ill. Application September 20, 1957, Serial No.685,201

5 Claims. (Cl. 209-418) This invention relates ingeneral toclassifyingdevices,

"and has more particular referenceto skips/or buckets having aclassifyinggrid therein'which'. serves to classify -fines from largeraggregate in the handlingrof dump loads of unclassified material, theinvention pertainingrmore especially to the mechanismfor receiving'dumploads of unclassified material and elevating, agitating, :classifying,and feeding the loads to a crusherainletxand a crusher bypass inlet,whereby fines are classified. from the loads-and delivered. to thebypass .inlet =andLthe-"Iarger aggregate isdelivered to the crusherinlet.

The requirement for-millionsx'of tons1oft1concretecaggregate' materialsfor thebuildingof highways hasevolved themarket and manufacture of:portable crushing and sc'reeningplants which may be used in rock :pitsalong the right of way of the highways :for the "purpose of T procuring:the necessary aggregate materials. The crush- -ing plants are generallyof the gravity-flow variety-which requires a g'ravity'diiferential toenable processing'of/the I rock,'this diiferential being generallygained through-elevation by shovel loading, ramp loading, hopper andelevator loading,"-all of which decrease the flexibility, portability,=and the capacity of the unit. Further,-a classifying feeder isnecessary to transport the'rock directly into -An important object-ofthe present invention is to p'rovide a me'chanismiof the character.mentioned which decre'ases the cost of operating: a portable crushingplant ax/hereby 'transfer -ofxrockifrom'ra truck'to arportable crush'erwill accomplish all fOf a the actions :h'eretofore necessitating the useof several mechanisms.

Anotherdmportant object is to provide amechanism for agitating,elevating;classifying and feedinga load of unclassified material into aportable crusher in 0ne-action.

- A=further object=of thefinvention is to provide a mechanism tolie-used :inflcombination with a rock crusher whichreceivesa load of"rocks and in onev motion elevates; a'gitat'es, classifies and feeds therock into-a crusher and crusher bypass--hopper.

Another important object is to provide a classifying device for use incombination with portable-rock crushers r 'having a": skip or bucketequipped with-a .scalping :grid

therein which. separates the fines from the. larger. aggre- ..:gateduring veleva'tion'ofthe skip to dump'the load by ,gravity feedinto aportable crusher and crusher bypass h pl t I i A further object of thisinventionis to provide'a'clas'm- 2,919,804 Patented Jan. 5, 1960 2i'fyingldevicenihaving a:bo.ttom, upstanding front, rear andiside'..walls,'and arscalping grid therein defining a chamber :into.--which fines areseparated from the larger aggregate, 1 :and: an?opening;at.o ne end of the chamber for emptying "crusher. inlet and anoutlet communicating with the crusher sdischarg'e, andwmechanis'mforreceiving dump loads of unclassifiedlmaterial, :andelevating, agitating,classifying, and feeding the loads -to..the crusher inlet'and the bypass-.-inlet, ;whereby,fines areiclassified from theloads and delivered.,toxthe bYPassinlet and'the larger aggregate is 'delivered;to thecrusher inlet, said mechanism compris- .ingazskip-having afibottom,upstanding front, rear and side swalls, saidfront and: rear walls beingat an incline frornithei' bottom -md away from each other, said .rearwallrextending substantially above. said front wall, aclassifyingLgridinsaid :skip extending between the;side walls and,fromtsaid bottom alongsaid backswall but in :spaced relation therefromto define achamber into which :fines-a-re' classified,--and. a chamberoutlet in said back wall-satroneend of said chamber adapted to empty theclassified lines into said bypass inlet whenremptying the skipyand:mea'nsufor elevating-saidskipfrom a ground receiving position to araised dumping positi'omsaid means tiltingwsaidaskip duringelevatingthereof thereby causing agitationwand classifying 'of'the load.

:The: foregoing and numerous 1 other important objects,

advantages, Sandwinherent. functions .of; the invention will become"apparentas thevsame: is more. fully understood from thefollowingdescription, which, taken inconnec- "tlOn 'WllI'h':-th6accompanying drawings, discloses a .preferred embodiment of theinvention.

:Referring to the drawings.

Fig. "1 is a fragmentary and partially diagrammatic view: ofa; portablecrushing 3 plant embodyingrthe' invenr tion;

EigLisa fragmentary and diagrammatic viewcof'the portable crushing plantof Figrl: and illustrating certain of the parts in various positions;

lFigs. -3, 4,- and 5 are side'elevational-views of the classifyingdevice 'according tothe invention and. illustrating various positions:of i .the deviceibetween .cground position and dump position and themanner in which: classi- Fig. .11 is .aifragmentary and partiallydiagrammatic ..view*of'-.a portable rock crushing plant illustrating theoperation. of the modified classifyingdeviceof Figs. 8,

. 9, and :10.

.Totillustrate the invention, the drawings show, especially in Fig. l, aconventional. dump. truck .10 emptying. its

vloadzintora skip orbucketof. the-mechanism 11.of the present inventionwhich servesto elevate, agitate, classify .andffeed the dump load intothe rockcrusher 12. Ex-

emplary operation of this crushing plant wouldflbe. in locating theportable crusher and classifying device at- .tagche'd thereto at a pointnear the rock source but: re-

mote to the extent that it would not interfere with' the removal of therock from the'rock'source, whereby the rock "would "be initially loaded"onto "dump" trucks which would transport the rock in its unclassifiedstage to the site of the crushing plant.

The portable crusher 12 includes a frame 13 mounted on wheels 14 whichrender the crusher mobile. A primary crusher 15 is supported on theframe which includes a crusher inlet 16 and a crusher discharge 17. Ahopper or crusher bypass l8 surrounds the primary crusher 15 andincludes a bypass inlet 19 and a bypass outlet or discharge 20 whichcommunicates with the crusher discharge 17 and a common discharge 21.The bypass permits fines that may be classified from the largeraggregate to bypass the primary crusher 15.

Attached to the portable crusher frame 13 is the classifying device 11which includes a classifying skip or bucket 22. Upper and lower links 23and 24 are pivotally mounted on one end of the frame 13 and at the otherend to the skip 22 in such a manner that when a hydraulic cylinder 25pivotally mounted on one end to the frame 13 and on the other end to anintermediate point of the lower link 24 is operated, the skip 22 will beelevated and tilted from ground position as seen in Fig. l to dumpposition as seen in Fig. 2 whereupon fines 26 are emptied from the skip22 into the crusher bypass 18 and the larger aggregate 27 is emptiedinto the primary crusher 15. This arrangement permits, if desired, threeclassifying devices 11 to be employed at the same time on three adjacentsides of the crusher for classifying and feeding loads of unclassifiedmaterial into the crusher.

Referring now to Figs. 3, 4, 5, 6, and 7, a classifying skip or bucket22A to be used with the classifying device 11 includes a bottom 28adapted to normally rest the skip on the ground at the ground position,a front wall 29, a rear wall 30, and upstanding side walls 31, 31. Thefront and rear upstanding walls 29 and 30 are inclined away from eachother and form obtuse angles With the bottom 28 as seen most clearly inFig. 3, and the rear wall 30 extends a substantial distance above theupper edge of the front wall 29. As seen most clearly in Fig. 6, theinclined front wall 29 includes oppositely extending triangularly shapedwing sections 32, 32 the outer upstanding edges which are connected tooutwardly flared side wall extensions 33, 33 for the purpose of giving awider opening into which the unclassified material may be initiallydumped. A cross piece or panel 34- extends between the upper ends of theside walls 31 from the forward edges of the side walls to the rear edgesthereof for the purpose of additionally reinforcing the skip and forother purposes to be hereinafter set forth.

A scalping or classifying grid 35 is arranged within the skip and inspaced relation from the rear wall 30 to define a chamber 36a whichreceives fines 26 separated from the larger aggregate. The grid 35comprises a plurality of longitudinally extending bars 36, arcuate inshape, and attached at their upper ends to the cross panel or piece 34and at their lower ends to the bottom 28. Accordingly, a more or lessconcave grid is defined by the arcuate bars 36 which forms a bottom forthe larger aggregate dumped into the skip. The chamber 36a is thereforedefined by the concave classifyIng grid 35, the bottom 28, the rear wall30 and the cross panel 34. It may be noted in Figs. 6 and 7 that thegrid bars 36 are tapered from their bottom ends to their upper endsthereby defining slots of varying width widening toward the upper ends.The upper edge of the back wall 30 terminates at 37 below the crosspanel 34 to define a chamber outlet or discharge 33 adapted to empty thefines from the chamber 36a when the skip is tilted to a dump position.As seen in Fig. 5, the chamber outlet 38 is so aligned with the portablecrusher as to empty the fines into the bypass inlet 19 when the skip isin dump position, while the larger aggregate is gravity fed into thecrusher inlet 16.

In operation, as the dump truck dumps its load into 4 the groundedupright skip, Fig. 3, the inertia of the dam action against the grid 35produces some separation of the fines from the larger aggregate. Theskip is then raised towards the crusher and gradually tilted during theraising operation thereby effectively rocking the load of unclassifiedmaterial against the grid 35. The rocking of the load upon the gridcauses agitation which effects additional separation of the finesthrough gravity and impact which work loose and drop through the gridwithout being squeezed within the load that otherwise would be movedover the grid. In this connection, the turning movement of the skipcauses the unclassified material on the grid 35 to roll over and thusaid in complete separation of fines from the larger aggregatecomponents. When the skip reaches the dump position, Fig. 5, the load isfully separated and then gravity fed with the oversize or largeraggregate entering the crusher inlet 16 and the fines entering thebypass inlet 19. The skip is then returned to a ground or load position,Fig. 3, to receive another dump load. Thus, in one action and with onemechanism, elevating, agitating, classifying and feeding of a dump loadto a crusher is accomplished.

In some instances it may be desired to further classify the fines,wherein a screen may be arranged between the scalping grid and the backWall of the skip thereby providing three classified discharge products.

Although the means for elevating and tilting the skip 22, Figs. 1 and 2is of a hydraulic mechanical type, it will be appreciated that otherwell known elevating and rolling skip devices may be employed, it beingappreciated that the specific mechanism used only performs the necessaryfunctions outlined above to give the proper elevating and tiltingaction.

A modified classifying skip or bucket 22B, shown in Figs. 8, 9, l0, and11, differs from the skip 22A only in the type of scalping gridemployed, and therefore will have identical parts identified by the samenumerals as applied to the skip 22A. The scalping grid of thismodification, generally designated by the numeral 35a, comprises spacedgrid bars 39 extending parallel to the rear wall 30. These grid bars 39are attached at one end to the cross panel 34 and at the other end tothe bottom 28 adjacent the lower end of the back wall 30 and therebydefine with these components a chamber 40 into which the fines areclassified. The operation of the skip 22B is substantially the same asthe operation of the skip 22A and is shown in Fig. 11, wherein the loadof unclassified material is dumped into the skip at ground position froma dump truck 10. The skip is then elevated and tilted during theelevating action to further classify and separate the fines from thelarger aggregate by rolling of the load during the tilting operation.When the skip reaches the dump position, the fines are sub stantiallycompletely separated from the oversize or larger aggregate and dumpedinto the bypass 18 while the larger aggregate is dumped into the crusher15. When the skip is emptied, it is relocated to the ground or loadposition for receiving another dump load from another dump truck.

It is thought that the invention and its numerous attendant advantageswill be fully understood from the foregoing description, and it isobvious that numerous changes may be made in the form, construction andarrangement of the several parts without departing from the spirit orscope of the invention, or sacrificing any of its attendant advantages,the form herein disclosed being a preferred embodiment for the purposeof illustrating the invention.

The invention is hereby claimed as follows:

1. A classifying device for segregating fines from larger aggregatecomprising an open topped bucket having rigidly interconnected bottom,front, rear and side walls, said front and rear walls being mutuallyinclined outwardly away from the bottom wall toward the open top of thebucket, said side walls having projecting ends extending outwardly ofthe terminal end of the rear wall, remote from the bottom wall, a crosspanel extending between and rigidly secured to said projecting ends ofthe side walls in position, spaced from the terminal end of the rearwall, to define a discharge opening between said panel and said terminalend of the rear wall, a classifying grid comprising a plurality ofspaced apart bars disposed between the side walls and extending betweenand secured rigidly at their opposite ends to said panel and said bottomwall in position, spaced inwardly of the rear Wall, to define a loadingchamber, in front of said grid, for receiving material to be classifiedwhen the bucket is in loading position, and a classifying chamber,behind the grid, into which fines may be delivered through the grid fordischarge thence through said opening in response to rearward tilting ofthe bucket from loading position to angularly tilted dumping position.

2. A classifying device as set forth in claim 1, wherein said spacedapart bars extend parallel with respect to the rear wall.

3. A classifying device as set forth in claim 1, wherein the spacedapart bars have end portions extending substantially parallel withrespect to the rear wall, adjacent the panel, and panel remote endportions bendingly inclined toward the front Wall at its junction withthe bottom Wall.

4. A classifying device as set forth in claim 1, wherein the rear wallis substantially longer than the front wall, and the front Wall, at itsend edge remote from the bottom wall, is wider than the rear wall, theside Walls being flared outwardly away from the bottom wall and adjacentthe front wall.

5. A classifying device as set forth in claim 1, including means forelevating the bucket from a loading position to a raised dumpingposition and for tilting the bucket rearwardly through an angulardisplacement substantially in excess of ninety degrees, to efiectclassification of the material while the bucket is being elevated andtilted between loading and dumping positions.

References Cited in the file of this patent UNITED STATES PATENTS291,395 Peggs Jan. 1, 1884 317,574 OConnor May 12, 1885 1,593,447Friedman July 20, 1926 2,567,389 MacDonald Sept. 11, 1951 2,764,292Austin Sept. 25, 1956

